Locking device



c. WHITE LOCKING DEVICE Aug. 5, 1941.

Filed July 22, 1939 INVENTOR L em'b mil? HIS ATTORNEY Patented Aug. 5, 1941 2,251,560 LOCKING DEVICE Cecil White, Sayre, Pa., assignor to Ingersoll- Rand Company, Jersey City, N. J., a corporation of New Jersey Application July 22, 1939, Serial No. 286,044

1 Claim.

This invention relates to locking devices, and more particularly to a locking device intended for preventing unauthorized movement of a rotary member.

One object of the invention is to secure a rotary member in position in a simplified manner and by means that are readily accessible and may be cheaply replaced if damaged or worn excessively.

Other objects will be in part obvious and in part pointed out hereinafter.

In the drawing accompanying this specification and in which similar reference numerals refer to similar parts- Figure 1 is a longitudinal elevation, partly broken away, of a pneumatic tool equipped with a locking device constructed in accordance with the practice of the invention,

Figure 2 is a transverse view taken through Figure 1 on the line 22, and

Figures 3 and 4 are perspective views of ele-- ments of the locking device.

Referring more particularly to the drawing, the invention is shown embodied, for the purpose of illustration, in a pneumatic percussive tool 20, as for example a riveter, having a casing 2| into an end of which extends a rivet set 22.

The casing is bored to receive a hammer piston 23 for actuating the rivet set 22, and inthe rearward end of the casing is suitable valve mechanism 24 for effecting the distribution of the pressure fluid whereby the hammer piston 23 is actuated.

The rearward end of the casing 2| also carries a grip member 25 which may be grasped for manipulating the tool 20, and in the grip member is an admission valve 26 for controlling the admission of pressure fluid into the tool. The valve 26 is of the slidable spring-pressed type arranged in a bushing 21 in the grip member and has a stem 28, the free end of which extends into a slot 29 in the grip member and terminates adj acent a lug 30 of a lever 3| pivotally connected to the grip member for unseating the valve 26.

The bushing 21 also serves as a seat for the valve 26 and is accordingly provided with a beveled seating surface 32 for a correspondingly shaped surface 33 on the valve adjacent the stem 28. In the bushing 21, rearwardly of the surfaces 32 and 33, is a port 34 to afford communication between the interior of the bushing and a pressure fluid supply conduit 35 threadedly connected to the grip member 25.

The admission valve 26 and the supply conduit 35 are located at the free end of the grip member 25, and from the bushing 21 leads a supply passage 36 that extends through the grip member to the distributing valve mechanism 24 for supplying pressure fluid thereto.

As will be readily appreciated, tools of the character described, and particularly those employed for light work, will operate efficiently and economically when actuated by pressure fluid of low value. Under many circumstances, however, the available supply of pressure fluid is of high value and it may, therefore, be desirable that means be provided to effect a reduction in the pressure of the fluid used for operating the tool. To this end the tool 20 is provided with a reducing or throttle valve 31 which, in the present instance, is threaded into and coaxial with a portion of the supply passage 36 to control the inlet end 38 of the lateral portion '39 of the passage 36 that leads to the valve mechanism 24. The throttle valve 31 is preferably in the form of a flllister-head screw and is threaded into and out of the supply passage 36 to partly cover and uncover the inlet opening 38, thereby reducing or increasing the flow of pressure fluid to the valve mechanism in accordance with immediate requirements.

The throttle valve 31 is preferably of such length that a considerable portion thereof, including its head 40, lies exteriorly of the casing 2| and is in substantial parallelism with the portion of the casing lying immediately forwardly of the grip member 25. The threads of the throttle valve 31 and those of the passage 36 wherewith it cooperates are of a tight fit to avoid leakage of pressure fluid to the atmosphere.

In order that the throttle valve 31 may be securely held against unauthorized rotation in the various positions that it may occupy in practice, the inner end surface of the head 43 of the throttle valve is provided with radial teeth 4| for engagement with similar teeth 42 of a locking plate 43. The locking plate is slidable on the throttle valve, which it encircles, and is constantly urged toward the teeth 4| by a spring 44 interposed between the plate 43 and a shoulder 45 on the casing 2|.

The aperture 46 in the plate 43 is preferably a loose fit on the throttle valve so that said plate may reciprocate freely relatively to the throttle valve for engagement and disengagement with the teeth 4| whenever the throttle valve is adjusted to a new position. On the edge of the plate 43 is a seating surface 41 which is shaped to conform with the adjacent portion of the periphery of the casing 2| and, in the assembled positions of the parts, lie closely adjacent said portion of the periphery of the casing to prevent rotary movement of the plate 33 whenever the throttle valve 3'! is rotated.

A suitable stop member, as for example a screw 68, may be threaded into the casing 25, forwardly of the head 38 to prevent accidental unthreading of the throttle valve from the passage 36.

In practice whenever the flow area of the inlet opening 38 requires adjustment the throttle valve 37 is rotated in either a right or left hand direction, and this movement of the throttle valve will cause the teeth it, by thrusting against the sides of the teeth 22, to move the plate out of engagement with the head of the throttle valve. The plate at will move freely along the throttle valve each time the teeth ti move over the teeth 42 but will be held against rotary movement by contact between the surface ll and the periphery of the casing 25.

Each time the crests of the teeth M move over the teeth 22 the spring it will immediately return the plate 3 to interlocking engagement With the head Ali and the throttle valve 3'3 will, therefore, always remain in any position to which it may be adjusted and Will not be efiected by the vibration resulting from the operation of the hammer piston 23.

I claim:

A locking device, comprising a casing, a mem- Iber threaded into the casing and having a portion lying exteriorly of the casing, a plate slidable on the member exteriorly of the casing and having a surface to conform with and slide upon the outer surface of the casing and to cooperate therewith for preventing rotary movement of the plate with respect to the casing, radial teeth on the opposed surfaces of the member and the plate interlockingly engaging each other to prevent rotary movement of the member, and a spring to press the plate into locking engagement with the member.

CECIL WHITE. 

